Education on the Dangers of Passive Smoking

Passive smoking causes approximately 50 000 deaths annually in the United States, with the vast majority of these deaths due to heart disease.1 The effects of secondhand smoke on many pathophysiological mediators of coronary artery disease are nearly as large as those of active smoking, including impaired platelet function,2 damage to vascular endothelium and its associated repair mechanisms,3 a rise in inflammatory molecules, and dysfunctional lipid metabolism (Figure).2 The large literature on passive smoking is not limited to cardiovascular disease. Passive smoking causes lung cancer, head and neck cancers, respiratory infections, and obstructive lung disease (chronic obstructive pulmonary disease, asthma) and has been linked with breast cancer in younger women.1,4 Although as of 2008, more than half of the United States was covered by legislation that limits tobacco use in public places and workplaces, the Centers for Disease Control and Prevention found that nearly one half of US nonsmokers continue to be exposed to secondhand smoke.5 Figure. Effects of passive smoking on biological mediators of vascular disease.2,3 NO indicates nitric oxide.Article p 1535 In this issue of Circulation , He et al6 document yet another example of the dangers associated with secondhand smoke exposure: peripheral arterial occlusive disease (PAOD). This is the first study to identify an association between exposure to secondhand smoke and the development of PAOD in any population, particularly among the nonsmoking Chinese women they studied. PAOD is a surrogate marker for coronary artery disease, resulting from similar pathophysiological mechanisms: development of atherosclerosis that leads to vascular stenosis and ischemia, which is manifested as claudication in the extremities. Given the similar underlying mechanisms, the results of the study by He et al6 are not surprising, but …